If branched-chain amino acids were a boy band, then leucine would be Justin Timberlake, and valine and isoleucine would be … those other guys.
Leucine has received so much hype over the last few years that many people opt to take straight leucine supplements over the complete complex of BCAAs. That could be a mistake, says recent research.
While leucine is a main instigator of post-workout protein synthesis, a study out of Oita University in Japan shows that isoleucine contributes to the burning of body fat. Subjects in the experiment were fed a high-fat diet. After isoleucine was added to the food, weight gain and fat-tissue growth was reduced and organs and muscle tissue showed signs of utilizing more stored fat.
While leucine also helps you stay lean, through raising metabolic rate, the combination of all of the BCAAs seems to possess more fat-fighting horsepower when taken together than when consumed separately.
A good dose of BCAAs for strength and physique athletes is 10 grams once or twice daily.